During the early to mid-1980s, car manufacturers, under pressure to increase fuel economy and simultaneously reduce emissions, switched to electronic fuel injection to obtain more precise control of engine fuel under all operating conditions. When the automotive aftermarket saw the trend, it entered the field, first with PROM chips that allowed the buyer to modify the constants programmed into the electronic controller unit at the factory by simply switching chips. This allowed one to increase performance somewhat, generally at the expense of gas mileage, and to make engine modifications for which changes in program parameters were needed. Gradually, conversion kits were developed to allow hobbyists and racers to upgrade carbureted engines to Electronic Fuel Injection (EFI) or to replace OEM Electronic Control Units (ECUs) to obtain much more control over the system than the re-programmed PROM chips allowed. One of the first of these was U.S. Pat. No. 4,494,509 (1985) to Long. Although now plentiful, these kits are quite costly and difficult to install and configure. Numerous drivability problems whose solutions are beyond the capabilities of the users are also often reported after the installation. Furthermore, the price of these systems places them well beyond the reach of most hobbyists and enthusiasts.
The present invention provides an engine controller that is: more cost effective because of its low parts count due to integrated technology; simpler to install because of its generic design and flexible software, allowing it to be used with all models and makes of engines from motorcycles to trucks, even or odd number of cylinders, and regardless of the experience of the end user. The design is also more reliable because of several software algorithms that will be described.